Oil Pump: Description and Operation

The oil pump has the following characteristics:
- It is a positive displacement intermal gear pump using top seal rotors (known as a gerotor oil pump).
- It is mounted on the front face of the cylinder block.
- The inner rotor is piloted on the crankshaft post and is driven through flats on the crankshaft.
- System pressure is limited by an integral, internally-vented relief valve which directs the bypass oil back to the inlet side of the oil pump.
- Oil pump displacement has been selected to provide adequate volume to ensure proper oil pressure both at hot idle and maximum speed.
- Relief valve calibration protects the system from excessive pressure during high viscosity conditions, yet is designed to provide adequate lubrication under high-temperature and high-speed conditions.